It rarely improves above and beyond the level from which it had plummeted, though. More often you get tweaks to reduce the major annoyances to tolerable level. Which users then tolerate because, well, what other choice do they have when literally everyone is doing it?
What's really bad about this is that we (as in the software industry) have managed to teach people to hate updates, and a significant part of that is all the gratuitous changes to established UI flows. Many casual users dread updates now because they just want their shit to keep working like it always did. And this is how you end up with unpatched security issues.
Or that it improves silently between several versions. Or that it just keeps getting worse, and people are justified every time.
I don't know a lot about Apple. Android seems to be partially at each of those camps.